Not sure about Saudi. but people travelled with GC + original extension letter returned back without any issues.

@HOPE U really need to be sure of Saudi Arabia 🇸🇦 particularly before going there. The way I was treated with a valid GC, honestly I wouldn't travel down there with Extention letter.

I’ve traveled countless time outside the US with my expired green card + original extension letter over the past 1.9 months that my card is expired I and I have had no issues (traveled for leisure in different countries, and travelled about 5times to France, my home country)

@Jennie . tnx for your response, but u mean Saudi Arabia or some where else

I traveled to Yemen and back with out issue. so u can go don’t worry